HI C. Pierre Orantes,
I'm a paying customer just like you -- so l'd like to add to your comments or questions and maybe answer some.
Zoiper version 5.x is an improved version from previous versions of Zoiper as far as appearance and I'm glad that the developers stayed away from skeuomorphism. So thanks to developers for a better product.
So now to your comments:
I agree with point 1. In the forums I've seen developers say that they're working on that but has been a long time coming.
As for point 2; you are using the compact mode; there is an expanded side on the right. You can click the current call in the list to see the expanded side or disable compact mode by going to settings, theme, then uncheck "enable compact mode". There is also a small arrow at the bottom of the contact list to expand and collapse the window. Once expanded you can now see a larger Call and Hangup buttons.
Point 3: You can directly input a number to call in search box and then press enter on keyboard. It is true that you need to press the keypad button on the soft-phone to enter TouchTones (DTMF) but once pressed and the keypad is displayed, you can use the number pad on your keyboard to enter tones or use the mouse.
Point 4: It sounds like you haven't seen the expanded window side; this is where that information is displayed except number of calls. More details of placed calls are also there like call duration.
I don't have Bluetooth headsets so no comment.
Improvements and fixes I'd like to see are:
Being able to use DTMF while in a conference, being able to call the same number and conference them, be given a visual indication as too who is taking while in a conference -- like Skype does. Fix the mute button; doesn't work while in conference.
Decrease or get rid of the delay between hangup and ready to place another call or redial the same number.